1. Field of the Invention
The present invention relates to a printing machine capable of selectively performing double-side (perfect) printing and single-side (simple) printing on a continuous web of paper (called xe2x80x9ccontinuous webxe2x80x9d or merely xe2x80x9cwebxe2x80x9d hereinafter).
2. Description of the Related Art
A conventional printing machine of the kind mentioned above includes, for example, a double-side surface printing machine in which two printing units are disposed, via a turning device for changing a side of the web to be printed, on a traveling path for the continuous web, in which a single-side surface of the web is printed by one of these two printing units. Then the web is turned by a turning device, and the other single-side surface thereof is thereafter printed by the other one of the two printing units, thus performing double-side (perfect) printing.
Another conventional example of such a printing machine is disclosed in Japanese Patent Laid-open (KOKAI) Publication No. 168035/2000 utilizing two printing units, in which web traveling paths in these two printing units are continuously connected so as to provide a hook shape or to be in parallel to each other in such a manner that a terminal end of a preceding printing unit is arranged to be continuously connected to a starting end of another succeeding printing unit through a turn-bar mechanism. According to such a printing machine, a single-side surface of the continuous web is printed by one printing unit and, thereafter, the web is turned by the turn-bar mechanism, and then the other single-side surface is printed by the other printing unit.
However, in the conventional printing machine of the structure mentioned above in the former example, in a case where only single-side surface printing is required on one continuous web, one of two printing units is not used, and hence, in such a case, the printing rate is made worse and deteriorated, and thus becomes rather inconvenient.
On the other hand, in the later mentioned conventional example, single-side surface printing can be performed by each of these two printing units, so that the printing machine is suitably applicable as a single-side printing unit. However, the two printing units in this example are arranged so as to be in hook-shape or in parallel to each other, so that a large amount of location space is needed.
The present invention was conceived to substantially eliminate the defects or inconveniences encountered in the prior art machines mentioned above and provides a printing machine including two printing units capable of carrying out double-side surface printing, and in the case of single-side surface printing, both printing units can be utilizedas single-side surface printing units, to thereby improve printing efficiency with a relatively small location space or site.
This and other objects can be achieved according to the present invention by providing, in a main aspect, a printing machine comprising:
two printing units, each comprising a web feed section, a web printing section connected to the web feed section and a web treating section as like as a web wind-up section connected to the web printing section, in which single-side surface of a continuous web is printed at each of the web printing sections; and
a turn/transfer section formed between the web printing section and the web treating section of one of the printing units, for turning and transferring the continuous web, which is printed by one of two web printing sections, to the other one thereof through turning and transferring operation of the continuous web.
In another aspect of the present invention, there is also provided a printing machine comprising:
first and second printing units, the first and second printing units comprising first and second web feed sections, first and second web printing sections connected to the first and second web feed sections, respectively, and first and second web treating sections connected to the first and second web printing sections, respectively, in which single-side surface of a continuous web is printed at each of the first and second web printing sections; and
a turn/transfer section formed at an intersecting portion between a first portion between the first web printing section and the first web treating section and a second portion between the second web feed section and the second web printing section, in which the continuous web printed at the first web printing section of the first printing unit is turned and transferred in a cross-over manner to the web second printing section of the second printing unit.
In a further aspect of the present invention, there is also provided a printing machine comprising:
first and second printing units, the first and second printing units comprising first and second web feed sections, first and second web printing sections connected to the first and second web feed sections, respectively, and first and second web treating sections connected to the first and second web printing sections, respectively, in which single-side surface of a continuous web is printed at each of the first and second web printing sections, wherein each of the first and second web feed sections of the first and second printing units is arranged at a portion on single-side in a direction perpendicular to a printing direction in the web printing section through one turning bar and each of the first and second web treating sections of the first and second web printing units is arranged at a portion on another single-side in the direction perpendicular to the printing direction in the printing section through another turning bar; and
a turn/transfer section formed at a connecting portion between the first and second web printing sections which are arranged on a same linear line, so as to transfer the continuous web printed at the first web printing section of the first printing unit to the second web printing section of the second printing unit as it is or in a turned state.
In the printing machines mentioned above, each of the first and second web printing sections includes a printing device and a drier disposed on a downstream side of the printing device.
The first and second printing units may be driven sectionally synchronously or independently.
According to the printing machine having the characteristics mentioned above, two, i.e. first and second, printing units perform the single-side printing operations independently. By utilizing the turn/transfer section, the continuous web which has been printed on a single-side surface at the one (first) printing section of one (first) printing unit is turned and transferred, in the cross-over manner, by the turn/transfer section, to the other (second) printing section of the other (second) printing unit, at which the other single-side surface is printed, thus double-side surfaces are printed.
Therefore, according to the printing machine of the present invention, in which single- or double-side printing operations can be selectively performed, two printing units can be independently utilized to thereby improve the driving (working) performance of the printing machine.
Furthermore, according to the arrangement in which there is disposed the turn/transfer section between the printing section and the continuous web feed section of one of the printing units so as to turn and transfer the continuous web, printed by the printing section, to the printing section of the other of the printing units, both the printing units intersect at their intermediate portions, thus making compact the printing machine itself and hence reducing the necessary installation space.
Particularly, in the arrangement in which the web feed section is disposed on a single side in the perpendicular direction to the printing section and the continuous web treating section is disposed on the other side in the perpendicular direction of the printing unit, the installation space can be further minimized.
The above and other objects, and nature and further characteristic features of the present invention will be made more clear from the following descriptions made with reference to the accompanying drawings.